Rain does fall from heights of several thousand feet, but by the time raindrops reach the ground, they are moving much more slowly than many people imagine.
A falling object does not keep accelerating indefinitely. Air resistance pushes upward and increases as the drop speeds up. Eventually, the upward drag force balances gravity, and the raindrop reaches a constant speed called terminal velocity. For typical raindrops, this is only about 15–30 km/h (10–20 mph), and even the largest drops rarely exceed about 35 km/h (22 mph).
Fgravity=Fdrag
Several factors make rain harmless:
Raindrops are very small and have very little mass.
Air resistance limits their speed.
Large drops tend to break apart into smaller drops before they become too fast.
The kinetic energy of a raindrop is tiny, so the impact on your skin is negligible.
By contrast, larger objects such as hailstones can hurt because they are heavier and can maintain higher speeds, carrying much more energy when they strike.
So, although rain originates thousands of feet above the ground, air resistance prevents raindrops from becoming dangerous.
